1-Azido-4-Phenyl-1,4-Butanedione as a convenient precursor for the synthesis of various nitrogen heterocycles

1 -AZIDO-4-phenyl-1,4-butanedione 2 proved to be a convenient precursor for the synthesis of a variety of heterocyclic systems through its treatment with some acidic and basic reagents. For example, 2-benzazepine-1,5-dione 3, 1,3-oxazolane-2,4-dione 4a, 1,3-thiazolane-2,4-dione 4b, 1,3-oxazol-5-one 5, quinazoline-2,4-dione 7, 4,6-diaryl-2-pyrimidineones 9a-d, 2,5-bis-substituted amino-1,3,4-oxadiazole II,5-aryl-2-N-substituted amino-1,3,4-oxadiazoles 13a,b, 1,2,4-triazol-3-ones 14a,b, 1,3-benzoxazine-2,4 [3H]-dione 15 and 1,3,4-oxadiazol-2[3H]-ones 16a,b